Electrical sostenuto piano



June 23, 1931. s. COOPER ,0

ELECTRICAL SOSTENUTO IPIANOV 7 Filed March 25, 192'! 2 Sheets-Sheet 1 June 23,1931. s. COOPER 1,811,076

ELECTRICAL SOSTENUTO PIANO Filed March 25, 1927 2 Sheets-Sheet 2 83 5 V lwwroz Patented June 23, 1931 SIMONYCOOPER, 01Ev BROOKLYN, NEW YORK A ELECTRICAL sos'rmw'ro PIANO Application filed men 25,

This invention relates to the electrical operation of stringed instruments, and, more particularly, the invention aims to provide certain improvements in the art of electrical 5 piano operation wherein there is employed a pulsator adapted to be acted on by string vibration and in circuit with an electro-mag net thefluctuating field of which acts on a string when such field is varied in strength.

Another object'of the invention is to provide an improved method and apparatus for obtaining'sostenuto as the result of the employment of such field.. i

Another object is to provide an improved 1 method andcapparatus for thus obtaining sostenuto without relying necessarily upon an initial impact or blow against the string such as is commonly delivered by the familiar hammer of the ordinary piano action; and in this connection it is also an object of the invention to provide a method and apparatus .wherein, for very quick building up of the note to full volume,the equivalent of a vibration-initiating percussively-acting fmechanical implement is employed. This equivalent, as I prefer to carry out the invention to at tain the object last mentioned, is an electrical means which may be used as a complete substitute for said mechanically acting implement. a Another object is to provide an improved method and apparatus for obtaining sostenuto electrically,

the string vibration, the hammer will be actuated in part at least by electrical means, and wherein, preferably, such j electrical means is adapted to insure automatic damp,- ing of the string vibration at the cessation of the sostenuto. V a

Another object is to provide'an improved method and apparatus as last stated, whereby a single simple movement may be performed, as the depression of a piano key,for the purpose of first initiating thes'tring vithat by closing wherein, a if such hammer blow or anequivalent be employed to startthe instrument may then 1927. 'Srial No. 178,209.

bration by a powerful blow or an equivalent, and then sustaining such vibration, as the result preferably of first setting up a more powerfulmagnetic field and then setting up a less powerful magnetic field.

Further to explain the various objects so far specifically mentioned:

In var1ous copending applications of mine which'relate to electrical sostenuto in pianos,

I have disclosed and claimed various types of pulsators, various mounts for the same, and various methods and means for operating such pulsators by or with the string and for directly or indirectly connecting such pulsators to the string and to different poran tions thereof. These applications include Ser. Nos. 17 8,204, and others, filed on even date herewith. y

In these applications, as sufliciently understood from the one particularly identified, as

the method disclosed in each case involved first the use of the piano hammer in initiating the vibration of the piano string and next the use of a pulsator for sustaining such vibration. I have discovered, however, that when the controllers are sensitively adjusted, according to the teachings of certain of said copending applications, it is not necessar I to employ a hammer to strike the string, an

the electric circuitcontaining the pulsator and magnet, the string is sufficiently put inmotion, although beginning with a very slight amplitude, to actuate the pulsator, and rather quickly, by way of the magnetic field fluctuation thus initiated, in an crease the successive current undulations to' the sound volume required. The magnet may be placed opposite the string'in any por tion of its length, but preferably at a poini for sounding, not only the fundamental but also partials as desired from the string. The ulsator is located on any vibratile portion of the string, either a singing portion or a ortion beyond a bridge. The operation of be likethat of a 99 piano organ, that is a key may to bring about, directly, the desired note, sostenuto. tainment oi the proper vibration of the musical member to a full musical tone is a cumulative process, occupying an appreciable period of time; and the invention also provides, where it is desirable to have the musical member or string attain full power extra quickly, a method and apparatus involving the employment 01 a striker or hammer im plemeut to be impa ted against the string, or a plectrum implement to vibrate the string as in a liiarpsichord, and involv'ng the actuation of such implement by elect= cal and say electromagnetic means. find the invention further proposes, as another example of a mode of causing the string to attain full power extra quickly, the employment of an auxiliary more powerful magnet, or a temporary i .crease of the current through the sostenuto causing me 7 t, during the initiatory stage of the string s vibration.

Another object of the present invention is to provide an improved method and apparatus having certain or all of the advantages just indicated, and wherein th equivalent of tl'n'ee-handed laying or piano organs or other musical ins ruments having practically no natural or in. t soslenuto, may be accomplished in the ordinary percussive-type of piano, so that one or more notes may be sustained as long as desired while the players two hands are occupieo with the piano keyboard to sound other notes or groups of notes.

Various other objects and advantages of the invention will be specifically pointed out or apparent hereinafter, in the course a description of several preferred of the various possible forms of tie invention as shown in the accompanying drawings; it be ing understood, of course, that such "forms are merely illustrative of combinations and arrangements of parts calculated to at.;aii the objects of the invention, pursuant to present preferences, and hence the etailed description of such forms now to be given is not to be talren as at all defining orlimiting the invention itself. That is to say, the scope of protection contemplated is to be talron solely from the appended claims, interpreted as broadly as is consistent with the prior art, and with explanatory references to the specification only where a claim is ambiguous or to be impliedly limited beyond its express terms to avoid such art in order to save the validity of said claim.

In the accompanying drawings:

Fig. 1 is a diagrammatic view illustrating one form of apparatus acz'sording to the in-- vention.

Fig. 2 is a similar form of apparatus.

Fig. 2a is a detailed View showing on an be depressed sounding of the However, the atview, showing another enlarged scale certain of the parts of Fig. 2.

Fig. 3 is a view similar to Figs. 1 and 2, but showing another form of apparatus.

Figs. 3a, 3?), 3c and 3d are detail views showing certain of the parts oi 3, said 3d being a section, on a slightly enlarged scale, taken on line 3(Z3(Z 01? Fig. 30.

Figs. 1 and 5 are views similar to Figs. 1, 2 and 8, showing, respectively, other forms of apparatus according to the invention.

Referring to Fig. 1, which shows an elementary form of apparatus capable oi. carrying out the method of the invention according to which an ordinary sostenuto pulsator may be employed as the sole means for initiating string vibration and then for sustaining such vibration, there are disclosed, as in Figs. 2, and 5, a piano string 10 stretched over bridge pieces 11 and 12. As in Figs. 2, E3 and l, this string of Fig. 1 has associated therewith an electromagnet 13 and a pulsator 14 in a common circuit including a suitable source of energy 15 and a switch 16 operated by the piano key 17 when the latter is depressed, as by rocking it about its pivot 17a. The pulsator may co-act with asinging or non-singing portion of the string 10.

In operation, an arrangement such shown in Fig. 1, I have found, results in the initiation of string vibration and the satisfactory building up of sostenuto, with the latter continued as long as the key 17 is held depressed, since thereby the switch. 16 is maintained closed the same length of time. On first closing the switch, there is set up such an electrical disturbance and in such proximityto the string, due to the sudden setting up of a magnetic field in the electromagnet 13, that enough of a vibratory movement is imparted to string 10 to act on pulsator 1ato cause an appreciable current lluctuation in circuit 15. This in turn causes another change in the magnetic held, and one more pronounced so far as giving a vibratile impulse to the string is concerned The result is a. greater current fluctuation in the circuit than the first one. This cross cumulative action continues, of course, much more rapidly than can be stated,- and I have found that satisfactory musical performance of most if not all compositions may be had in this way on an electrical sostenuto piano.

Referring now to Fig. 2, an arranqen'ient is here shown wherein a hannner H other than the ordinary hammer of the piano ac tion, is employed for the initial blow against the string 10, when it is desired to build up the full sostenuto musical tone very quickly. This arrangen'ient of Fig. 2 also includes a damper D for the string operating at the proper instant by the same means which actuates the hammer, here an auxiliary electro-magnet 18 in the circuit including battery 15 and the sostenuto magnet 13.

This magnet 18 acts to attract an armature 19 when the key switch 16 is closed; said magnet 18, as shown, being more powerful than the sostenuto magnet 13.

' Armature 19 and damper D are on a pivoted arm 20. The hammer H, and a latch 21, are pivoted, for relative movement when required, on ashaft 22. The pendent limb of latch 21 is engaged by the upper end of arm 20 when the armature is attaracted by the magnet 18 upon the closing of the circuit; it being understood that suitable means, springs (not shown), urge the parts to the normal positions illustrated. The attraction of magnet 18 for armature 19 is sufficient to carry the arm 20 beyond and out of engagement with the latch with the result that the hammer strikes a blow upon a string 10 and instantly rebounds. The sostenutois set up. and maintained, however, by magnet 13, as long as key 17 is held depressed. Arm 20 returns to its normal position when the key is released, and the arm 20 moves back past latch 21, without disturbing the hammer, but to seat the damper against the string to silence the latter.

Referring to Fig. 3, the arrangement here 7 shown includes a powerful magnet 18 as in energizing the sostenuto circuit and thenhrows the plate 267) beyond the p n 28, perplate 26a is Fig. 2, but closer to the piano string; and a separate circuit including its own source of electric energy 23 and a pair of terminals 24: and 25; Attached to key 17 is a contact latch 26 which depends resiliently from a flexible arm 27. v

, Referring to Figures 30. and 3d, this contact latch includes a conducting-bridge plate 26a bevelled at its bottomas indicated at 26a, and carrying a rearwardly extending guide plate 26?). Near the oottom of the ltrough between these two plates, as indicated in Fig. 3d, is a release opening 28a for the free end of a fixed pin 28 after the latter has been trapped in the V-trough. Such trapping is incident to a part of the operation of the contact latch as will now be explained. f r

When the key 17 is depressed the bridge forced into contact with the terminals 24 and 25, as the result of the pin 28 engaging the ramp constituted by the outside surface of plate 26? thus causing a powerful momentary energization ofmagnet l8,

and a considerable vibratory movement of the string .10.

Further and completedepression of key 17 first closes the switch 16, causing current to be supplied to pulsator 14 and magnet 13, thus mitting the bridge plate 26a to move away from the terminals 2 1'and 25 thus breaking the circuit through magnet 18.

Upon releasing the key 17, the pin 28 engages the inclined inner surface of the guide plate 26?) and insures the clearing of the bridge plate 26a from the terminals 24 and without contact ,ever, the equivalent 25; the pin passing through the opening 2811 located in the V-trough, and all the parts thus becoming reset for another depression of ke 17.

eferringto Figs. 3, 3a and 31), there is shown an arrangement for three handed playing as in plane organsgwhereby key 17 may have associated with it an auxiliary key 29, e

which when once set into operative condition as an incident to a depression of said key 17, remains thus until the operated; whether or not the key 17 is then depressed or undepressed. In the present case this arrangement for three-handed playing includes, in addition to these two keys, two contacts 30 and 31. standing rigid stud on key .17, desirably bevelled at its top as indicated; and contact31 is a fairly rigid horizontal wedge-piece, carrying a lug 31a, and suspended by a band-spring 315 or the like from key 29. so arranged that when the two keys are in normal position, that is, both undepressed as shown in Fig. 3 there is a break in the shunt 32 including magnet 13; and the arrangement of the parts is also such that with key 29 undepressed, key 17 may be depressed 3O touching contact 31. When, however, key 29 is depressed while key 17 is already when it is desired to lock the key 17 depressed to release the finger which depressed it for the depression of another key 17, the contacts 30 and. 31 not only touch, but snap into temporary latch-lock as shown in Fig. 3a. When now the key 17 of Fig. 3a is released to return to its normal position as shown in Figs. 3 and 3b,'the interlocking of the contacts 30 and 31 is still held; and will continue to be held, until key 29 is rocked in the opposite direction about say a central pivot (not shown), whereupon the parts 31a will snap free of contact 30, and the condition shown in Fig. 3 will berestored.

The described arrangement provides for what is sometimes called three-hand playing.

auxiliary key is again Contact 30 is an up-' These parts are e in depressed position, as

orfor duet performances on a single piano sincewhen akey such as 29 is depressed to close the shunt circuit, the sostenuto will be maintained for that particular string while the performer may remove his finger from the main key to depress other keys; and the sostenuto effect may be discontinued at any time by releasing the key 29.

Obviously,'the elements 29 to 32, or equivalents, may be employed with the arrangement of Fig; '1; as also with the arrangements of Figs. 1 and cated at 29 to 32 on the latter.

These Figs. 4 and 5 havecircuits somewhat like those of Fig. 3, yet but a single magnet, the sostenutomagnet 13, is employed. Howof the arrangement of that in Fig.4 a more is employed for the in- Fig. 3 is present, in powerful battery 23 5 now to be described, as indiitial vibration and the usual magnet 15 is enipioyed for the sostenuto; and in th t lr'l Fig.

' lypowert'ul battery 23 in i used for the initial vibrato s i and a part on of this battery, as indicated at 28a, is us for the sostenuto.

. v) are 3 1 which connects l inai of the b cry 23, the

, or to 'niiual of this battery being connected to the lead to puts-inter 1e from battery 1 Upon iirst depressing 1!, the uppe 16 is torced into center:

14. leai 16a of s vitcl with spring 33 cursing a heavy charge 0? battery 23" throu i pulsator 11 and iii 1511c and thus C2 is;

string stronglv to vibrate. F'dl'tilbl' deression 01". he 1'? breaks the circuit for inittcry 23 at and 53 1, again 0511153111 the string .10 to vibrate. Complete deprc i cocci/u r w h W Le it brings spring 33 and lost 16?), causing now oi current from the battery to flow through the pulsator and mag :tor the so net, in Fig. 5, the circuit .tor main sostenuto is thro L p the pulsator, the nnignet,

cal 35, the p01 tion 23a of battery 23, switch 16, and lead A conductor 3'? leads on: magnet 13 to a spring 38 which hours upon anothc spring' 39, connected. by a rod 39a with. key 1?. A contact 10 leads to the end of batterv 523 opposite to the end thereof connecting with lead 35. A stop prevcntr-i the spring- 88 from mov; to; all the v down with spring 39; so th spring is left hehind when springs 39 and touch. 'lhus, duri 1g depression of the key, magnet 13 receive a powerful surge of current from battery 23", due to the contact of spring 39 with springs Br and. 10, and then said magnet receives the sostenuto current from battery-portion 2365 only, due to the closing of switch 16 and the passing on of springs 39 -10 beyond spring; 38 when the latter engages stop 11.

Dninpcr means, in 2, may obviously be employed re arrai. enien'ts of .F 1,, 4: and f as by using; another magnet, in circuit vith the sostenuto magnet and the puisator, and acting when. energized to atct arn'ieture mounted for movement with ti o damp-er means, as

via

2, so that W116i! the two magnets are Clo-energized on releasing key 17, the damper restored to its normal engz cement with string; 10.

Inasmuch many could be made in the noove constructions, and many apparently widely different embodiments of my invention could be made without departing from the scope thereof, it is intended that all matte contained in the above description or shown in the accompanying drawings shall be interpreted as illustr: tive and not in a limiting sense.

It is also to be understood that the lauguage *ont-uined in the following claims intended to cover all the generic and specific natures of the invention herein described l all statements of the scope of the invenwhich, as matter of language, might be ical mus cal instrument, the i a vib a 'ing strnw, a

sical in truinent, the ting striny', a key, a

t, y, an

on of n vibr: source 01' current supp l L l electro-nnignct string an initial vibration :ith said source it n'uignet n5; nornzaily out or circuit, and 7 when the lie is partially deuzd source and ct are put in her depressed a magnet are restored to norsaid circuit.

instrrinent, the

iir

1i mu st in, a stuns;- operas d pulsatt i, u lie a source 01 Cllt'l't'ilb supply, an 6180131'0ll18gl16t for giving the string an initial vibration when in circui u with said sou e, said niagiiet and source sing; norinell out o'':' circuit, and means opthe hey for making such circuit and enter by then for in g such circuit and then for dumping the string vibration.

The instrument defined in claim 1, wherein there provided a percussive inun- Jner, and s: it magnet actuates said hnnnner when the ltev is operated to 111211 16 said circuit.

Th instrunmit defined in claim 1, wherein there provi ed a, percussive haininer, and said magnet actuates said hammer when the hey operated to make said circu t, there also being providec a mechanical 1 camper for the string;

octi when the key is operated to break sau circuit.

The instrument defined in claim 3,

Wlldl'Oll'l there proided u percussive haminer, and. said magi et aculates said hunnner when the key is operated to make said circuit, there also being provided a mechanical damper for the string actuated when the key is operated to break said circuit.

7. The instrument defined in claim 1,

wherein there is provided a percussive hummer and a mechanical damper, and said magnet actuates said hammer when the key is operated to make said circuit, there being means associated with the hammer and damper whereby when the key is operated to make id circuit the hammer is retract-ed imniei tcly at V3 striking the string and the damper is actuated when the key is permitted to break the circuit.

8. In an electrical sostenu combination of a vibration-i for the string, and a sostenuto means for the string, said two means including three eiements of which two are magnets and the third is a source of current supply.

9. In electrical sostenuto piano, the combination of a vibrating-initiating mcans for the string, and a sostenuto means for the string, said two means including three eleto piano, the

ments a first of which elements is a magnet,

a second of which elements is a source of current supply, and the third of which elements is a magnet more highly energized than the first named said first and second elements,

said third element and the element whereof it is a type being of different powers.

10. In an electrical sostenuto piano, the combination with a string, and with means including a movable member and a normally inoperative electrical means rendered operative for sostenuto on moving said member from a first position to a second position, of a second movable member, and means associated with the two movable members whereby both members may be moved to lock the first member in said second position, for three-handed playing.

11. The piano defined in claim 10, wherein the means last mentioned includes co-acting devices rendered inoperative by a predetermined movement of the second movable member, thereby to release the two members from the lock.

12. The method of producing sostenuto effeet in a piano string which consists in establishin g a preliminary strong electro-magnetic string plucking field adjacent the piano string and thereafter causing pulsator variations in em. l field in phase with the vibrations of the string.

13. The method of producing sostenuto effect a piano string which consists in causing an electric current to produce a preliminary magnetic string plucking field and thereafter maintaining the current and causing the vibrating string to produce pulsator variations in thestrength of the current to effect corresponding variations in the strength of the magnetic field.

14. The method of producing sostenuto effect in a piano string which consists in causing an electric current to produce a preliminary magnetic string plucking field and thereafter maintaining the current and causing the vibrating string to eflect the production of a .tiating means switch means under second and variable magnetic field inphase with the vibrations of the string and acting on said string. 7 y

15. Themethod of producing sostenuto effect in a piano string which consists in causing an electric current to produce a preliminary magnetic string plucking field and thereafter maintaining the current and causing the vibrating string to effect the production of a second and variablemagnetic field in phase with the vibrations of the string and acting on said string, the second field difiering in intensity from the first.

16, In a sostenuto piano or the like, a string, a plucking magnet, a pulsator actuated by the string, a sostenuto magnet, a power source, a key, and switch means under control of the key for actuating the plucking magnet and for actuating the sostenuto magnet under control of the pulsator.

the like, a

17. In a sostenuto piano or magnet, a pulsator actustring, a plucking ated by the string, a sostenuto magnet, a power source, a key, switch means under control of the key for actuating the plucking magnet and for actuating the sostenuto magnet under control of the pulsator, a hammer, and a hammer actuator including a damper, the plucking magnet being arranged to operate on the hammer actuator.

18. In a sostenuto piano -or the like, a string, a plucking magnet, a pulsator actuated by the string, a sostenuto magnet, a ower source, a key, switch means'under control of the key for actuating the plucking magnet and for actuating the sostenuto magnet under control of the pulsator, a hammer, and a hammer actuator including a damper, the plucking magnet being arranged to operate on the hammer actuator, and the hammer having a trip device giving a hammer stroke when the actuator is moved in one direction and permitting the actuator to move in the other direction to apply the damper without movement of the hammer.

19. In a sostenuto piano or the like, a string, a pulsator actuated by the string, a sostenuto magnet, a power source, a key, control of the key for actuating the sostenuto magnet under control of the pulsator, andmeans for mamtaining the sostenuto without continued manual depression of the key.

20. In a sostenuto piano or the like, a string, a pulsator actuated by the string, a sostenuto magnet, a power source, a key, switch means under control of the key for actuating the sostenuto magnet under control of the pulsator, a shunt in the circuit of the sostenuto magnet and pulsator and a second key for closing and opening the shunt circuit, to maintain sostenuto without continued depression of the main key or to discontinue the sostenuto.

21. The piano defined in claim 16 with the SIMON COOPER. 

